﻿using System;
using System.Collections.Generic;
using System.Text;
using System.Web;
using System.Drawing;

namespace Product.Common
{
    public class CodeBar
    {
        public void ProcessRequest(HttpContext context, int length)
        {
            if (length != 0)
            {
                this.length = length;
            }

            //VerifyCode v = new VerifyCode();
            this.Length = this.length;
            this.FontSize = this.fontSize;
            this.Chaos = this.chaos;
            this.BackgroundColor = this.backgroundColor;
            this.ChaosColor = this.chaosColor;
            this.CodeSerial = this.codeSerial;
            this.Colors = this.colors;
            this.Fonts = this.fonts;
            this.Padding = this.padding;
            string code = this.CreateVerifyCode();        //取随机码
            this.CreateImageOnPage(code, context);        // 输出图片
            context.Session["VerifyCode"] = code;
            //string saltValue = "#@(**WEF";//请勿更改
            //code = EncryptHelper.GetMd5Hash(code.ToUpper(), saltValue);  //加密验证码到cookie
            context.Response.Cookies.Add(new HttpCookie("VerifyCode", code));// 使用Cookies取验证码的值
        }

        #region 属性
        int length = 4;
        public int Length
        {
            get { return length; }
            set { length = value; }
        }

        int fontSize = 12;
        public int FontSize
        {
            get { return fontSize; }
            set { fontSize = value; }
        }

        int padding = 1;
        public int Padding
        {
            get { return padding; }
            set { padding = value; }
        }

        bool chaos = true;
        public bool Chaos
        {
            get { return chaos; }
            set { chaos = value; }
        }

        System.Drawing.Color chaosColor = Color.LightGray;
        public System.Drawing.Color ChaosColor
        {
            get { return chaosColor; }
            set { chaosColor = value; }
        }

        System.Drawing.Color backgroundColor = System.Drawing.Color.White;
        public System.Drawing.Color BackgroundColor
        {
            get { return backgroundColor; }
            set { backgroundColor = value; }
        }

        System.Drawing.Color[] colors = { System.Drawing.Color.Black, System.Drawing.Color.Red, System.Drawing.Color.DarkBlue, System.Drawing.Color.Green, System.Drawing.Color.Orange, System.Drawing.Color.Brown, System.Drawing.Color.DarkCyan, System.Drawing.Color.Purple };
        public System.Drawing.Color[] Colors
        {
            get { return colors; }
            set { colors = value; }
        }

        string[] fonts = { "Arial", "Georgia" };
        public string[] Fonts
        {
            get { return fonts; }
            set { fonts = value; }
        }

        string codeSerial = "3,4,5,6,7,8,a,c,e,f,j,k,m,r,s,u,v,w,x,A,B,C,E,F,G,H,J,K,M,N,Q,R,S,T,U,W,X,Z";
        public string CodeSerial
        {
            get { return codeSerial; }
            set { codeSerial = value; }
        }

        private const double PI = 3.1415926535897932384626433832795;
        private const double PI2 = 6.283185307179586476925286766559;
        #endregion

        /// <summary>
        /// 正弦曲线Wave扭曲图片（Edit By 51aspx.com）
        /// </summary>
        /// <param name="srcBmp">图片路径</param>
        /// <param name="bXDir">如果扭曲则选择为True</param>
        /// <param name="nMultValue">波形的幅度倍数，越大扭曲的程度越高，一般为</param>
        /// <param name="dPhase">波形的起始相位，取值区间[0-2*PI)</param>
        /// <returns></returns>
        public System.Drawing.Bitmap TwistImage(System.Drawing.Bitmap srcBmp, bool bXDir, double dMultValue, double dPhase)
        {
            System.Drawing.Bitmap destBmp = new System.Drawing.Bitmap(srcBmp.Width, srcBmp.Height);

            // 将位图背景填充为白色
            System.Drawing.Graphics graph = System.Drawing.Graphics.FromImage(destBmp);
            graph.FillRectangle(new System.Drawing.SolidBrush(System.Drawing.Color.White), 0, 0, destBmp.Width, destBmp.Height);
            graph.Dispose();

            double dBaseAxisLen = bXDir ? (double)destBmp.Height : (double)destBmp.Width;

            for (int i = 0; i < destBmp.Width; i++)
            {
                for (int j = 0; j < destBmp.Height; j++)
                {
                    double dx = 0;
                    dx = bXDir ? (PI2 * (double)j) / dBaseAxisLen : (PI2 * (double)i) / dBaseAxisLen;
                    dx += dPhase;
                    double dy = Math.Sin(dx);

                    // 取得当前点的颜色
                    int nOldX = 0, nOldY = 0;
                    nOldX = bXDir ? i + (int)(dy * dMultValue) : i;
                    nOldY = bXDir ? j : j + (int)(dy * dMultValue);

                    System.Drawing.Color color = srcBmp.GetPixel(i, j);
                    if (nOldX >= 0 && nOldX < destBmp.Width
                     && nOldY >= 0 && nOldY < destBmp.Height)
                    {
                        destBmp.SetPixel(nOldX, nOldY, color);
                    }
                }
            }

            return destBmp;
        }

        public System.Drawing.Bitmap CreateImageCode(string code)
        {
            int fSize = FontSize;
            int fWidth = fSize + Padding;

            int imageWidth = 63;// (int)(code.Length * fWidth) + 4 + Padding * 2;
            int imageHeight = 22;// fSize * 2 +Padding;

            System.Drawing.Bitmap image = new System.Drawing.Bitmap(imageWidth, imageHeight);

            Graphics g = Graphics.FromImage(image);

            g.Clear(BackgroundColor);

            Random rand = new Random();

            //给背景添加随机生成的燥点
            if (this.Chaos)
            {

                Pen pen = new Pen(ChaosColor, 0);
                int c = Length * 10;

                for (int i = 0; i < c; i++)
                {
                    int x = rand.Next(image.Width);
                    int y = rand.Next(image.Height);

                    g.DrawRectangle(pen, x, y, 1, 1);
                }
            }

            int left = 0, top = 0, top1 = 1, top2 = 1;

            int n1 = (imageHeight - FontSize - Padding * 2);
            int n2 = n1 / 4;
            top1 = n2;
            top2 = n2 * 2;

            Font f;
            Brush b;

            int cindex, findex;

            //随机字体和颜色的验证码字符
            for (int i = 0; i < code.Length; i++)
            {
                cindex = rand.Next(Colors.Length - 1);
                findex = rand.Next(Fonts.Length - 1);

                f = new System.Drawing.Font(Fonts[findex], fSize, System.Drawing.FontStyle.Bold);
                b = new System.Drawing.SolidBrush(Colors[cindex]);

                if (i % 2 == 1)
                {
                    top = top2;
                }
                else
                {
                    top = top1;
                }

                left = i * fWidth;

                g.DrawString(code.Substring(i, 1), f, b, left, top);
            }

            //画一个边框边框颜色为Color.Gainsboro
            g.DrawRectangle(new Pen(Color.Gainsboro, 0), 0, 0, image.Width - 1, image.Height - 1);
            g.Dispose();

            //产生波形
            //image = TwistImage(image, false, 8, 4);

            return image;
        }

        public void CreateImageOnPage(string code, HttpContext context)
        {
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            Bitmap image = this.CreateImageCode(code);

            image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);

            context.Response.ClearContent();
            context.Response.ContentType = "image/Jpeg";
            context.Response.BinaryWrite(ms.GetBuffer());

            ms.Close();
            ms = null;
            image.Dispose();
            image = null;
        }

        public string CreateVerifyCode(int codeLen)
        {
            if (codeLen == 0)
            {
                codeLen = Length;
            }

            string[] arr = CodeSerial.Split(',');

            string code = "";

            int randValue = -1;

            Random rand = new Random(unchecked((int)DateTime.Now.Ticks));

            for (int i = 0; i < codeLen; i++)
            {
                randValue = rand.Next(0, arr.Length - 1);

                code += arr[randValue];
            }

            return code;
        }

        public string CreateVerifyCode()
        {
            return CreateVerifyCode(0);
        }
    }
}